Tire gauge



' s- 26, 1930- P. w. PFEIFFER 1,774,153-

Illa GAUGE Filed Aug. 51, 1921 N g: a Tlllllllilllillllllll N TOR.

ATTORNEYS,

Fatentecl Aug. 26, 1936 I rnrnnfw= rrnrrrnn, orsvnnonsn new YORK i m was r 7 Application .file d nugust 31, 1927. seen no. 216,688.

This invention relates to pressure gauges particularly gauges for I indicating the pressure in pneumatic-tires, and has for itsobject a 'gaugewhich'is particularly simple and econoniicalin construction and hi hly efiiclent and -durable1n use and also asun- 'ple means for holding tllfl'lllCllCfltOl member in the'position it has been 'operatedibythe air pressure.

The invention consists the novel-features andin the combinationsand construction hereinafter set forth jandc laimedf v In describing this invention, reference is had to the accompanying drawingsin which like characters designate corresponding parts Figure is a detail view of the rigid washerforming part of the means for holding the indicator member in its operatedposition.

Figures 5, 6 and 7 aredetail views of the parts of the plunger or piston or the gauge. This gauge comprises, generally, a tubular body having an air inlet at one end, a plunger movable in the body and normally located at the inlet end, an indicator extending lengthwise of the. body through the other.

-Which is snugly fitted an annular corrugation or internal bead 13 on the tubularbody- 1.

end of the body and coacting atits inner end with the plunger, means for returning the plunger to its normal position, and means operated by thereturnlng means for holding the indicator in the position ithas beenopg erated by the plunger.

1 designates the tubular body having a head 2 at one end provided with an airinlet tube .3 which terminates in an air chucks to be applied to the valve stem of the tire when it is desired todetermine the pressure in the tire.

5 is'a head closing the other f end on the outer end of the tubular body,th is havingv an openingor slot 6 therein.

7. is a plunger or piston slidable in the body and normally located at the inlet end thereof. 8- is the indicator in the form of a rubber.

plunger 7. together. 7 diameter tha the head and the internal fitted into the body 1,'and thus form a piston 'blade extending lengthwise of the body' and contacting at its inner end withthe plunger and being 'CllSCOIlIlQClLQd'tllBI'GfIOfll, the blade extending throughth'e slot 6.x The'indicator is provided with suitable 'graduations'to in-; dicate the pressure, the partlcular graduationjfindicating the pressure, coming in line with the outer'snrface of the head'5.

p The meansfor returningthe plunger to its normal position at the lnner end ofthe body 1, is a coil spring 9 located within the body U encircling the indicator 8, the spring thrustin at one end a ainst the lun er 7 and its other end toward the head 5, and against meansfor holding the indicator8 in its operated position. This means being inter-l posed between the end of the spring and the head 5."

Thehead 2 is in the form of a cup in which the contiguous end of the tubular body is snugly fitted without screw threads. 1 The head'2 of the air chuck and tube 31 are an i integral structure. 3 The air chuck consists of a metal-plug 10 having a lengthwise passage 11, the plug being driven into the tube 3 and having a snug fit therewith so that the screw threads are not required. The plug 10 is surrounded by compressible sealing block or plug 12 of iyielding material as The head 5 is preferably interlocked with the outer end of the bodyfan-d is here illustrated as formed with an annular groove in The end or the tubular body-thrusts against a flangeor shoulder 14 on the head 5. The plunger 7 comprises a body or head 15 having an annular shoulder 16 and a stem 7 17 extending beyondthe shouldeig'a packing disk 18 on the'stem and a head or thickened washerQO, the end of t is stem 1? being spread into a countersink 21 in therhead or washer 20, and thus holding'all the parts of the The disklS is otgreatcr diameterof the body 1 in orderto fold over the'head or washer 20 when the plunger is packing;

ion

- ment tends to hold the indicator blade cen lit) - tered. The end of the bifurcations are bent lnwardly as in 23 so that their edges are not in line, and end I edges contact at 2% the end of the plunger 7. V

The means operated by the spring '9 for holding the indicatorin its operated position regardless of the position of the plunger 8, comprises a washer 25 of compressible material as felt arranged adjacent the inner face of thehead 5 and being of sullicient diwith anieter to fit, the internal body 1, and a metal. Washer 26 thrusting against the washer 25.

The spring 9 thrusts against the washer 26. The washers 25 and 26 are formed with slots through which the indicator 8 extends, these slotsbeing in line with slot 6 at the head The Washer 25 being of a compressible material, and being confined by the nead 5, washer 26, and walls of tubular body 1, tends to close the slot therein when the spring 9 is under pressure, and hence acts as a friction brake on the blade 8 to hold it in its operated position. I

In operation, the air chuck is applied to the valve stem of the tire and the air pressure passes through the tube '3 against the plunger and forces the plunger toward the outer end of the body 1 against the action of the returning spring 9 and in so doing forces the indicator outward during the compression of the coil spring 9. During the compression of the spring the felt washer is compressed and the walls of the slot therein contract on the indicating member so that when the gauge is removed from the valve stem of the tire, the indicator will remain in. its operated position-although the plunger 7 is returned to itsstarting position .under the influence of the spring 9. The operator takes the readin from thevraduation en the i blade in line with the outer edge of the head 5. The bifurcations of the indicator 8 together with the slots in the head 5 and washers 25 and 26 hold the blade centered and the bifurcations in particular hold the inner end of the indicator from undue lateral displacement,

lVhat I claim is:

1. A tire gauge comprising a tubular body having an air inlet at one end, a plunger movable in the body and normally located at the inlet end, the body havinga head at the other end formed with a slot, an indicator extending lengthwise of the body and normally coacting at one end against theplunger and extending at its other end through the slot,

the indicator being in the form of a blade having a bifurcated portion, bifurcations of which extend in opposite directions providend formed with a slot, an indicator extending lengthwise of the body and normally coacting at one end against the plunger and extending at its other end through the slot, the

' indicator being in the'form of a blade having a bifurcated portion, the bifurcations of which extend in opposite directions providing the blade with an enlargement, said bi fur-cations being located at the end of the blade adjacent the plunger and the ends of the bifurcations extending toward each other to contact with the plunger, and a returning springwvithintlie body and encircling the indicator, the spring thrustingagainst the plunger. I

In testimony whereof, I have hereunto signed my name at Syracuse, in the county of Onondaga and State ofNew Your, this 30th day of August, 1927.

PETER W. PFEIFFER. 

